Plants Clean Up More Air Pollution Than Previously Thought

Let's just take it as a given that plants are awesome in many practical and inherent ways and go from there: New research, led by scientists from the National Center for Atmospheric Research, shows that plants clean out air pollution to a much greater extent than previously thought. In fact, some types of trees actively consume certain types of air pollution.Looking at oxygenated volatile organic compounds (oVOCs)--which are emitted from both manmade and non-manmade sources and can have serious effects on the health of the environment and humans--the team found that deciduous plants take up oVOCs as much as four times more rapidly than previously thought. The canopies of dense forest actually are responsible for 97% of observed uptake of oVOCs.

Especially interesting is that certain types of trees--they looked at poplars--actually markedly increase their uptake of these chemicals when the tree is wounded or otherwise stressed, with the tree's metabolic cycle increasing.

Plants can produce chemicals to protect themselves from irritants and repel invaders such as insects, much as a human body may increase its production of white blood cells in reaction to an infection. But these chemicals, if produced in enough quantity, can become toxic to the plant itself. In order to metabolize these chemicals, the plants start increasing the levels of enzymes that transform the chemicals into less toxic substances. At the same time, as it turns out, the plant draws down more oVOCs, which can be metabolized by the enzymes.

Globally Over One-Third More oVOCs Consumed by PlantsAt the global level, plants are taking up 36% more oVOCs than has been accounted for in previous studies. This means that fewer of these compounds are evolving into aerosols, which has large implications for air pollution and climate change as aerosols play a significant role (both increasing and decreasing warming) in global warming.